Note: Descriptions are shown in the official language in which they were submitted.
2~.~~ ~~~
METHOD AND APPARATUS FOR CREATING AIR FLOW IN A WALL
OR CEILING FOR DRYING PURPOSES THROUGH AN
ELECTRICAL BOX OR THE LIKE
SPECIFICATION
Background of the Invention
Field: The invention is in the field of methods and
apparatus for drying building walls and ceilings, particularly
hollow building walls and ceilings that have become
undesirably wet through floods, pipe breakage, fire fighting,
or other disasters.
State of the Art: It is current practice in drying
hollow walls and ceilings that have become wet to direct a
flow of air against such walls or along such walls and
ceilings to draw water therefrom. In some cases an attempt
is made to circulate air through the walls or ceiling. This
is done by drilling or cutting holes or making slits in the
walls or ceilings and directing air toward such holes or
slits.
U. S. Patent No. 5,155,924 discloses special diverters
which can be placed over expansion slots in a floor or slots
made by removing a portion of a floor, or over holes cut
through a wall or ceiling to direct flowing air into the
floor, walls, or ceiling through such holes. The holes that
are made through the floor, walls, or ceiling, must be
repaired after the drying process.
Electrical boxes which mount electrical switches and
outlets to walls provide access to the inside of at least
portions of the walls. The inventor has found that he can
take off the face plate of electrical switches or outlets and
then pull the switch or outlet clear of the box and direct the
air from a blower toward the box to create some air flow into
the wall. With air merely directed from a blower toward an
2
electrical box, however, the transfer of air to the wall or
ceiling is very inefficient.
Summary of the Invention
According to the invention, air flow through a wall or
ceiling for drying purposes can be enhanced by apparatus which
can be secured over an electrical box to an electrical wall
switch or an electrical outlet in the box in place of the
normal face plate therefor or to an electrical box which
serves as a mounting for electrical lighting fixtures in place
of the lighting fixture and to a source of pressurized air to
provide a connection between the source of pressurized air and
the wall or ceiling. The air enters the wall through the
electrical box and flows through the wall to exit through any
openings (such as other electrical boxes) or cracks in the
wall. Most walls are not completely sealed and enough air
flow occurs to effectively dry the walls. Alternately, rather
than connecting the apparatus to a source of pressurized air
to create a flow of air into the wall through the electrical
box, the apparatus may be connected to a source of partial
vacuum or suction to draw air from the wall through the
electrical box. In such case, air enters the wall through the
various openings or cracks and f lows from the wall through the
electrical box to the source of vacuum. The use of electrical
boxes as inlets or outlets for air eliminates the need for
cutting holes in walls or ceilings in order to induce air flow
and thus eliminates the need for repair of such holes after
drying is completed as is required with methods of the prior
art. The apparatus of the invention includes a conduit body,
which may be fabricated or molded of a plastic material, and
which has a first end sized and configured to fit
circumferentially around a given electrical box. A second end
of the conduit body is configured to be attached to a source
of pressurized air, such as to a hose extending from the
output of the usual air blower used for drying purposes, or
3
to a source of vacuum, such as to a hose extending from the
input of the usual air blower used for drying purposes. An
air flow passage extends from the second end through the
conduit body and opens through the first end of the body to
the electrical box.
Electrical boxes are generally installed in a wall or
ceiling so that an open face of the electrical box extends
through a hole or opening in the wall or ceiling and is
usually substantially flush with an exposed surface of the
wall or ceiling which surrounds the open face of the box. The
conduit body includes means for securing it to an outlet or
switch mounted in the electrical box or to the box itself so
that the conduit body is secured over the box with the first
end of the conduit body abutting the wall or ceiling surface
around the box. The securing means will generally take the
form of appropriately placed screw holes through the conduit
body so that screws can be inserted to extend through the body
into the normally provided threaded holes in a wall switch or
outlet installed in a box or in the electrical box itself .
When the second end of the conduit is attached to a source of
pressurized air, the conduit provides a source of pressurized
air at the face of the electrical box. When the second end
of the conduit is attached to a source of a partial vacuum,
the conduit provides a partial vacuum at the face of the
electrical box. Either pressure or vacuum has been found very
effective in creating a flow of drying air in a wall or
ceiling. Since the source of pressurized air or vacuum
generally can move a substantial volume of air, it is not
necessary that the conduit body seal around the electrical
box. It merely has to provide substantial restriction to the
flow of air other than into or out of the box. Thus, the
holes for the mounting screws can extend into and through the
passage without substantially affecting the flow of air into
or out of the box. Further, it is not necessary to provide
sealing gaskets against the wall or ceiling, however, such
CA 02160766 2005-12-20
4
gaskets may be provided, and if provided by a thickness of
resilient material, may help compensate for variations in the
placement of the electrical box within the opening in the wall
or ceiling to facilitate installation of the device over the
electrical box.
The conduit body may be made in various shapes and with
various dimensions to fit specific electrical boxes, such as a
separate fixture sized to fit over a single width electrical
box with one model having two mounting holes spaced to
position screws to screw into a wall switch in the box in
place of the normal cover plate which is removed, and a second
model having a single mounting hole spaced to position a screw
to screw into a standard duplex electrical socket in place of
the standard socket wall plate. Separate models can be made
for double width electrical boxes and light fixture electrical
boxes. Alternately, a single conduit body may be sized to fit
around a variety of boxes with multiple screw holes located
therethrough to provide for mounting to any of the variety of
boxes.
The invention also provides a method of creating air flow
through hollow walls or ceilings for drying purposes by
providing apparatus to direct pressurized air into a wall or
ceiling through or around existing electrical boxes or to draw
air out of a wall or ceiling through or around existing
electrical boxes.
In another aspect the invention resides in an apparatus
for directing pressurized air into a hollow wall or ceiling
through an electrical box mounted in the wall or ceiling with
a surface of the wall or ceiling extending around an open face
of the electrical box, comprising: a conduit body having a
first end sized and configured to fit circumferentially around
the open face of a given electrical box and a second end
configured to be coupled to a source of pressurized air; an
air flow passage extending between and opening to the first
CA 02160766 2005-12-20
4a
and second ends whereby pressurized air entering the air flow
passage through the second end is directed to and leaves the
air flow passage through the first end; and means for securing
the conduit body over the open face of a given electrical box
so that the first end will substantially abut the surface
around the open face of the box.
In a another aspect, the present invention resides in a
method of creating air flow in a hollow wall or ceiling having
an electrical box installed therein with an open face thereof
in a receiving hole in the wall or ceiling which has a surface
surrounding the open face of the box, comprising the steps of
exposing the face of an electrical box; securing a conduit
apparatus having an end adapted to fit around the face of the
electrical box over the box so that the conduit apparatus
abuts the surface surrounding the face of the box and an air
flow passage in the conduit opens to the face of the box; and
supplying pressurized air to the conduit apparatus whereby the
pressurized air is forced into the wall or ceiling through and
around the electrical box.
In another aspect, the present invention resides in an
apparatus for applying a partial vacuum to a hollow wall or
ceiling through a preexisting opening in the wall or ceiling
with a surface of the wall or ceiling extending around an open
face of the opening, comprising: a conduit body having a
first end sized and configured to fit circumferentially around
the open face of a given opening and a second end configured
to be coupled to a source of a partial vacuum; an air flow
passage extending between and opening to the first and second
ends whereby a partial vacuum applied to the air flow passage
through the second end is directed to and causes a reduction
in air pressure at the first end; and means for securing the
conduit body over the open face of a given opening so that the
first end will substantially abut the surface around the
opening.
CA 02160766 2005-12-20
4b
In another aspect, the present invention resides in a
method of creating air flow in a hollow wall or ceiling having
an electrical box installed therein with an open face thereof
in a receiving hole in the wall or ceiling which has a surface
surrounding the open face of the box, comprising the steps of
exposing the face of an electrical box; securing a conduit
apparatus having an end adapted to fit around the face of the
electrical box over the box so that the conduit apparatus
abuts the surface surrounding the face of the box and an air
flow passage in the conduit opens to the face of the box; and
supplying a partial vacuum to the conduit apparatus whereby
the partial vacuum draws air from the wall or ceiling through
and around the electrical box.
In yet another aspect, the present invention resides in a
method of creating air flow in a hollow wall or ceiling
comprising the steps of providing an opening in the wall or
ceiling; securing a conduit apparatus having an end adapted to
fit around the face of the opening over the opening so that
the conduit apparatus abuts the surface surrounding the
opening and an air flow passage in the conduit opens to the
face of the opening; and supplying a partial vacuum to the
conduit apparatus whereby the partial vacuum draws air from
the wall or ceiling through and around the opening.
In a further aspect, the present invention resides in
an apparatus for creating a flow of air in a hollow wall or
ceiling through a preexisting opening in the wall or ceiling
with a surface of the wall or ceiling extending around an open
face of the opening, comprising: a conduit body having a
first end sized and configured to fit circumferentially around
the open face of a given opening and a second end configured
to be coupled to a source of pressure different from that in
the wall or ceiling; an air flow passage extending between and
opening to the first and second ends whereby a pressure
applied to the air flow passage through the second end is
CA 02160766 2005-12-20
4C
directed to and causes a difference in air pressure at the
first end; and means for securing the conduit body over the
open face of a given opening so that the first end will
substantially abut the surface around the opening.
The Drawings
The best mode presently contemplated for carrying out the
invention is illustrated in the accompanying drawings, in
which:
Fig. 1 is a perspective view of a room with a wall in
need of drying and showing a standard drying blower with a
special attachment plate of the invention used to connect
hoses to the drying blower to direct air to electrical boxes
in the wall through apparatus of the invention;
5
Fig. 2, a fragmentary vertical elevation of the special
attachment plate on the blower taken through a hose on the
line 2-2 of Fig. 1;
Fig. 3, a fragmentary vertical section taken on the line
3-3 of Fig. 2;
Fig. 4, a front elevation of an apparatus of the
invention which fits over an electrical box with wall switch
therein taken on the line 4-4 of Fig. 1, with the pressurized
air hose and clamp omitted, and showing structure behind the
apparatus in broken lines;
Fig. 5, a vertical section taken on the line 5-5 of Fig.
4, but showing the electrical box in elevation;
Fig. 6, a fragmentary perspective view of a portion of
the wall of Fig. 1, with electrical box having an electrical
wall switch therein and showing the apparatus of the invention
adapted to fit over the single electrical wall switch and
showing how it fits around the electrical box;
Fig. 7, a rear perspective view of the apparatus of the
invention shown in Figs. 4-6;
Fig. 8, a front elevation of an embodiment of the
invention adapted to fit over a single electrical duplex
outlet taken on the line 8-8 of Fig. 1, but with the
pressurized air hose and clamp omitted, and showing structure
behind the apparatus in broken lines;
Fig. 9, a vertical section taken on the line 9-9 of Fig.
8, but showing the electrical box in elevation;
Fig. 10, a front elevation of an embodiment of the
invention adapted to fit over a double wall switch;
Fig. 11, a front elevation of an embodiment of the
invention adapted to fit over a double electrical outlet;
Fig. 12, a front elevation of an embodiment of the
invention adapted to fit over an electrical box to which
electrical lighting fixtures are mounted;
Fig. 13, a horizontal section taken on the line 13-13 of
Fig. 12;
6
Fig. 14, a front elevation of an embodiment of the
invention adapted to fit over all of the various types of
switches, outlets, and electrical boxes shown in the previous
figures;
Fig. 15, a vertical section taken on the line 15-15 of
Fig. 14;
Fig. 16, a horizontal section taken on the line 16-16 of
Fig. 14;
Fig. 17, an enlarged fragmentary horizontal section of
a portion of Fig. 16;
Fig. 18, a rear perspective view of the apparatus of
Figs. 14-17;
Fig. 19, a front perspective view of the apparatus of
Figs. 14-17;
Fig. 20, a perspective view of a room similar to that
shown in Fig. 1 with a wall in need of drying and showing a
standard drying blower with special attachment plates of the
invention used to connect hoses to the input of the drying
blower to draw air from the electrical boxes in the wall
through apparatus of the invention;
Fig. 21, a fragmentary vertical elevation of the special
attachment plate on an inlet of the blower taken on the line
21-21 of Figure 20;
Fig. 22, a perspective view of an alternate embodiment
of the conduit of the present invention showing an elastomeric
foam seal; and
Fig. 23, a vertical section through the embodiment of
Fig. 22, and showing the conduit attached to an electrical
box.
Detailed Description of the Illustrated Embodiments
A standard, commercially available blower unit 20, Figs.
1 and 20, as used to circulate air in a room or blow air
against or along a wall, floor, or ceiling for drying purposes
includes a housing 21, an air intake opening 22, and an air
7
outlet duct 23 with outlet opening 24, Figs. 2 and 3. A grate
25 is secured in outlet opening 24 by screws 26. In normal
operation of blower unit 20, air outlet duct 23 is directed
to the portion of a room where air f low is desired and the air
exits the blower through outlet opening 24 and grate 25. For
example, if wall 30 had become wet because of a broken pipe
in the ceiling above the wall or because of a flood, the
blower outlet duct would be directed toward wall 30.
For use with the pressure embodiment of the invention,
it is desirable to have the air from the blower carried by
hoses 31 to apparatus of the invention which fits over
electrical boxes mounted in a wall or ceiling to provide
pressurized air to such boxes. For this purpose, a hose
mounting plate 32, Figs. 1-3, is placed over outlet opening
24 and is held in place by J-shaped locking members 33, Fig.
3, the stem of which rotatably pass through bearings 34 and
have a knob 35 on the end thereof so that knob 35 is
accessible to a user. A locking member 33 is positioned at
each end of plate 32, one of which is shown in Figs. 2 and 3.
The locking member at the other end of plate 32 is identical.
A spring 36 is positioned between plate 32 and knob 35 to bias
knob 35 and J-shaped locking member 33 outwardly which biases
the lower web portion of the J toward plate 32. With this
arrangement, plate 32 may be easily secured over the blower
outlet by turning the locking member so that the lower web
portion of the J extends along the long axis of the plate 32
as indicated at 37 in Fig. 2 where it can be pushed through
an opening 38 in grill 25. With plate 32 over outlet duct 23,
knob 35 can be pushed inwardly against the bias of spring 36
to push the lower web portion of the J through opening 38 to
the inward position 39 shown in broken lines in Fig. 3. In
this inward position, member 33 can be rotated as shown by
arrow 40, Fig. 2, to the locking position shown as 41 in Fig.
2. The knob 35 is released and spring 36 urges member 33
outwardly so that the lower web portion of J-member 33 abuts
8
the grill as shown in solid lines in Fig. 3 with the outer
hook portion of the J-member extending into grill opening 42.
With locking members in locking position at both ends of plate
32 , plate 32 is held securely across opening 24 in outlet duct
23.
Plate 32 has a number of nipples 45, Figs. 2 and 3,
extending therefrom over which an end 46 of a hose 31 may be
placed and secured such as by clamps 47, Figs. 1 and 3. Plate
32 as shown in Fig. 1 has six nipples for the attachment of
six separate hoses 31. These hoses can be directed to
different portions of a room. Depending upon the size and
output capacity of the blower 20, a plate 32 may provide for
attachment of fewer than the six hoses. Further, where more
nipples for hose attachments are provided than the desired
number of hoses for a particular job, caps may be placed over
the unused nipples.
For use with the vacuum embodiment of the invention, it
is desirable to have input air to the blower carried by hoses
163 from the apparatus of the invention which fits over
electrical boxes mounted in a wall or ceiling to provide a
source of partial vacuum to such boxes to draw air therefrom.
For this purpose, hose mounting plates or manifolds 160, Figs.
20 and 21, are fitted over the opposite air intakes 22 of
blower unit 20. Only one air intake 22 is shown in Fig. 1,
with one manifold over that intake in Figs. 20 and 21, but a
similar intake is generally provided on the opposite side of
the blower unit 20, as indicated by the hoses 163 extending
from such opposite side in Fig. 20.
The manifold 160 of the vacuum embodiment differs from
the manifold of the pressurized air embodiment in that the
manifold is shaped to fit over the air intake 22 of the blower
20 instead of over the air outlet duct 23 of the blower unit.
The manifold has a number of nipples 161 for the attachment
of hoses 163. The hoses may be secured in place by hose
clamps 164. Intake screens 162, Fig. 21, trap any large
~1~~ ~~
9
objects that may be picked up by the partial vacuum in the
hoses 163, thereby preventing any possible damage to the
blower 20.
In the event that not all nipples 161 of a vacuum
manifold 160 are used, extra nipples may be terminated with
a cap 165. The manifolds 160 are generally equipped with
elastomeric gaskets 166 that help ensure a seal between the
intakes 22 of the blower 20 and the manifolds 160. The vacuum
manifolds 160 are removably held in place on blower 20 by a
set of spring clips 167.
The basis of the invention is the finding that electrical
boxes as generally installed in walls and ceilings, and
sometimes in floors, open into the space behind the walls or
ceiling between studs on which the wall or ceiling is mounted
to an extent sufficient to allow air to flow through the
electrical boxes into or out of the interior of the wall or
ceiling for drying purposes. Typically, a wall is constructed
with a series of spaced, vertically oriented studs, one stud
50 being shown in Figs. 4-6, with plaster board 51 secured to
one side of the stud to form a wall 30, Fig. 1, and plaster
board 52 secured to the other side of the stud to form the
other side of the wall. An electrical box, such as box 53,
Figs. 4-6, is secured to the side of stud 50 such as by nails
54 extending into stud 50 through standard box mounting
bracket 55, Figs. 4 and 5. The open face of box 53 usually
projects into a hole or opening 56 in plaster board 51.
Electrical box 53 will generally have holes or openings
therein, such as holes 57, Fig. 5, through which wires can
extend and through which air can pass from the box into the
wall between plaster board 51 and 52. In addition, usually
hole 56 in the plaster board will be somewhat larger than the
perimeter of box 53 so there will be a small space between the
box and the plaster board, at least at the corners as
indicated in Fig. 1, where air can pass around the box into
the wall. Also, in many cases, wiring will extend along the
~16~'~~
inside of the wall with holes drilled through the studs for
the passage of such wires. Thus, if air is forced into a wall
through or around an electrical box, it will circulate at
least along and through parts of the walls or ceilings or
5 floors. Such circulation will be similar to the circulation
that could be obtained by cutting holes in the walls, ceiling,
or floor and forcing air into the walls, ceiling, or floor
through such holes. Similarly, if air is drawn out of a wall
through or around an electrical box, the air drawn out will
10 flow from and circulate along and through parts of the walls
or ceilings or floors as it flows to and out of the electrical
box.
In the particular arrangement of Figs. 4-6, a standard
electrical wall switch 58 for operating room lights is shown
mounted in usual fashion in electrical box 53 by screws 59.
For normal use, a standard switch cover plate, not shown,
would be placed over box 53 and opening 56 and held in place
by two screws which would extend into screw holes 60, Fig. 6,
provided in switch 58 specifically for that purpose. Switch
toggle 61 extends through a slot in the cover plate so is
accessible to be operated by a user. These switches and cover
plates are in universal common use in most buildings in the
United States.
With the present invention, the standard switch cover
plate is removed and a special apparatus or conduit 62, Figs.
4-7, of the invention is secured over the electrical box 53
and opening 56. This is done without removal of the switch
from the electrical box. Conduit 62 has an opening 64 in a
first end 65 thereof. The outer dimensions and configurations
of first end 65 are such that this first end will be bigger
than and thus extend around opening 56 in plaster board 51
with the first end 65 abutting the wall or ceiling surface
surrounding opening 56 and electrical box 53. Opening 64
confronts the open face of electrical box 53, and preferably
is approximately coextensive with opening 56 in plaster board
~~~7~
11
51. Switch toggle 61 extends into opening 56. Conduit 62 has
a second end 66 which is conf figured to be attached to a source
of pressurized air. In the embodiments shown, second end 66
is configured as a nipple to receive a hose end 67 of a hose
31 thereover, Figs. 5 and 6, (or a hose end 67 of hose 163)
with a clamp 68 provided, if necessary, to securely clamp hose
end 67 to nipple 66. Opening 64 in conduit body first end 65
extends into and through the second end 66 to form an air flow
passage extending between and opening to the ffirst and second
ends of the conduit. Thus, conduit 62 serves as an adapter
attached to the end of an air hose to fit the end over an
electrical box and to secure the end to an electrical box.
Conduit body 63 includes two holes 70 therethrough which
are spaced similarly to the two holes 60 in wall switch 58.
With the first end of conduit body 63 placed over electrical
box 53, and with wall switch 58 still secured in normal
fashion therein, holes 70 through conduit body 63 are aligned
with holes 60 of wall switch 58. Screws 71 are inserted
through holes 70 and screwed into holes 60 just as screws
holding a normal switch face plate would be. Thus, conduit
62 is a replacement for the face plate normally used for a
wall switch and is easily secured over the wall switch.
To use the conduit apparatus 62 of the invention as shown
in Figs. 4-7, the normal wall switch face plate is removed and
the conduit is placed over the switch and secured thereto with
screws 71. The conduit first end 65 will extend against or
abut the wall around the perimeter of the hole 56 with
electrical box 53 therein to substantially restrict air flow
between first end 65 and the wall. With a hose 31 secured to
the second or nipple end 66 of the conduit, pressurized air
as supplied by blower 20 will be forced into the wall through
electrical box 53 and between electrical box 53 and the edges
of box receiving hole 56. With a hose 163, Fig. 20, secured
to the second or nipple end 66 of conduit 62, a partial vacuum
is created by blower 20 which will draw air from the inside
2~~~'~~~
12
of the wall through electrical box 53 and between electrical
box 53 and the edges of box receiving hole 56.
Rather than a wall switch being mounted in electrical box
53, a standard duplex outlet 75, Figs. 8 and 9, could be
mounted therein by screws 76. With a standard outlet, an
outlet cover (not shown) is usually mounted over the
electrical box 53 and mounting hole 56. In the case of an
outlet, however, a single screw extends through the outlet
cover to be screwed into a standard receiving hole 77 between
the outlet faces 75a and 75b. Figs. 8 and 9 show an
embodiment of the conduit of the invention specifically
configured to fit over a duplex outlet 75. Conduit body 78
includes a bar 79 extending centrally through opening 80 in
the first end of the conduit, from side-to-side, with a hole
81 therethrough positioned to be aligned with the standard
hole 77 in the outlet 75. A screw 82 is inserted through hole
81 and screwed into outlet hole 77 to secure conduit body 78
over the electrical box 53 as with the light switch. With the
embodiment for use with an outlet, however, screw 82 is
inserted through the air flow passage 83 from the opening in
the second end 85 of the body. This has to be done before
hose end 67 is placed over second end 85.
The electrical box 53 as shown in Figs. 4-6 and 8 and 9
is a single box sized to accept one standard wall switch or
one standard duplex outlet therein. Another commonly used
electrical box is a double box 90 as shown in Figs. 10 and 11.
The double box is designed to hold two standard wall switches
91 and 92, Fig. 10, held in side-by-side relationship by
screws 93 or two standard duplex outlets 94 and 95, Fig. 11,
held in side-by-side relationship by screws 93. These double
boxes 90 are secured to stud 50 in a wall in similar standard
fashion as indicated for the single box, but the hole in the
plaster board or other wall material is larger to accept the
larger electrical box.
21~~ i~ i
13
With two standard wall switches 91 and 92 in a box as
shown in Fig. 10, a standard face plate is normally placed
over the box and secured in place by four screws which are
screwed into the standard screw holes 99 provided in the wall
switches for that purpose. A conduit 96 of the invention
specifically configured for use with double wall switches has
a first end 97 sized to fit around a double electrical box as
shown in Fig. 10. While four screw holes could be provided
for four screws to extend into the four holes provided in the
wall switches, two holes through which screws 98 can be
inserted and screwed into two of the four standard wall switch
screw holes 99 is generally satisfactory to secure conduit 96
over the electrical box. A vertical section through Fig. 10,
as indicated by the line 5-5 on Fig. 10, would be
substantially the same as the vertical section through a
single wall switch conduit as shown in Fig. 5, however, Fig.
5 is numbered for Fig. 4 rather than for Fig. 10.
With two standard duplex outlets 94 and 95 mounted in box
90 as shown in Fig. 11, a standard outlet cover is normally
placed over the box and secured in place by two screws which
are screwed into the standard screw holes provided in the
outlets. A conduit 100 of the invention specifically
configured for use with double outlets has a first end 101
sized similarly to that of conduit 96 to fit around a double
electrical box as shown in Fig. 11. In this case a bar 102,
similar to bar 79 of Figs. 8 and 9, extends through the
opening 103 in first end 101 with holes therein positioned to
be aligned with the standard outlet holes so that screws 105
can be inserted through such holes and screwed into the
standard outlet holes to secure conduit 100 over the outlets.
Screws 105 are inserted from inside the opening 106 in the
second end 107 of conduit 100. Again, a vertical section
taken on the line 9-9 of Fig. 11 will be substantially the
same as a vertical section through a single outlet conduit as
shown in Fig. 9, however, Fig. 9 is numbered for Fig. 8 rather
14
than Fig. 11, except that indentation 108 in Fig. 9 (a similar
indentation is provided on the corresponding opposite inside
portion of conduit 100 not shown) represents an indentation
in the conduit 100 of Fig. 11, to make it easier to insert
screws 105 through bar 102 and into the side-by-side socket
holes.
In some cases, triple boxes are used to mount three wall
switches in the wall of a room. A similar attachment
configured to fit over and be secured to the light switches
in a triple box could be provided.
In the case of light fixtures in a ceiling, as shown in
Figs. 12 and 13, an electrical box 110 is usually mounted in
a hole 111 in the ceiling 112 and is secured to a ceiling beam
113 such as by nails 114 extending through a usual mounting
bracket 115. A ceiling light fixture (not shown) is usually
secured over the box on the ceiling by two screws threaded
into holes in box tabs 116. The building wiring 117 is
usually connected to the light fixture wiring (not shown) in
the electrical box 110 generally using wire nuts (not shown).
For forcing air into a ceiling or for drawing air from a
ceiling, the light fixture is removed from over the box by
unscrewing the screws and the wires disconnected so that the
fixture is removed from the box and the ceiling. A conduit
120 of the invention with a first end 121 sized and conf figured
to fit over and around electrical box 110 and ceiling opening
111 is positioned over box 110. Holes are provided through
conduit 120 aligned with the standard holes in tabs 116 and
screws 122 are inserted through the holes in the conduit and
screwed into the holes in tabs 116 as shown in Figs. 12 and
13 to secure conduit 110 to the electrical box so that the
first end 121 thereof abuts the ceiling 112 peripherally
around ceiling hole 111. As with the other embodiments of the
conduit of the invention, the second end 123 of the conduit
is configured to receive the end of a hose supplying
pressurized drying air or the end of a hose connected to a
15
source of partial vacuum. An air passage 124 extends from
communication with the second end of the conduit to the first
end of the conduit where it opens through the first end in
confronting relationship to the box 110 and ceiling opening
111.
As described so far, a separate embodiment of the
invention has been provided for each separate size of
electrical box and for mating with wall switches or outlets
mounted in such boxes. A further embodiment of conduit of the
invention is sized and configured to be used universally with
any one of the one switch or one outlet size box, two switch
or two outlet size box, or the normal ceiling fixture box.
As shown in Figs. 14-19, a conduit 130 has a generally
rectangular first end 131 and generally rectangular opening
132 therein. Thus, first end 131 forms a rectangular flat
surface extending around opening 132 and adapted to abut a
wall, ceiling, or floor peripherally around an electrical box
of single or double switch or outlet size, or of ceiling box
size, with the box and wall, ceiling, or floor hole for the
box opening into and communicating with the conduit opening
132. The second end 133 of the conduit is formed as a nipple
134 to receive the end of an air hose thereon, as with the
previously described embodiments. As with the embodiments of
Figs. 8, 9, and 11, a bar 138 extends through opening 132.
In order to secure the conduit 130 over a variety of
electrical boxes, a plurality of mounting holes is provided
for selective use depending upon the particular arrangement
of switches, outlets or light fixtures in the electrical box
to be covered. Two holes 140 are provided to align with the
holes of a single wall switch. To mount conduit 130 over a
single wall switch screws are extended through holes 140 into
the standard threaded receiving holes in the wall switch.
Holes 141 are aligned with two of the holes of a side-by-side
arrangement of wall switches and would provide the mounting
screw arrangement of Fig. 10. Holes 142 are aligned with the
~1~~~C
16
holes provided in the tabs of a standard ceiling box and
provide the mounting screw arrangement of Figs. 12 and 13.
Central hole 143 in bar 138 provides for mounting over a
single duplex outlet as in Figs. 4-6. Holes 144 in bar 138
provide for mounting over a side-by-side arrangement of
outlets as shown in Figs. 8 and 9. Again, indentations 145
in the inside surface of conduit 130 provide more room for
mounting of screws through holes 144.
While with any of the mountings of conduit 130 over an
electrical box several or all of the holes 140-142 will be
open and allow communication between the opening 132 and the
outside atmosphere, it has been found that the size of such
holes does not allow enough pressurized air to escape to
interfere with the flow of air into the walls or ceiling or
to allow enough air to be drawn into the hose to interfere
with the flow of air drawn from the walls or ceiling. Thus,
the presence of these open holes is not a problem.
A further embodiment of conduit of the invention which
eliminates the need for a bar, such as bar 138 in Figs. 14-19,
and which includes elastomeric material about its first end
for facilitating installation over a variety of electrical
boxes installed at a variety of depths in a wall, is shown in
Figs. 22 and 23. Conduit 170 has a generally rectangular
first end having a generally rectangular opening 171 therein
that fits about an opening in the wall 172 containing an
electrical box of single or double switch or outlet size, or
of ceiling box size, as with the embodiment of Figs. 14-19.
The conduit has a second end 173 in the shape of a nipple and
adapted for attachment of an air supply or vacuum hose. The
conduit is provided with a plurality of mounting holes 174 in
various patterns such that the conduit may be attached to a
variety of electrical boxes of single or double switch or
outlet size, of ceiling box size, or to switches mounted in
an electrical box. In addition, holes 185 are provided for
securing the conduit to a variety of outlets mounted in
~16~'~~
17
electrical boxes. If a single duplex outlet is to be covered,
the conduit 170 is placed off-center over the outlet so that
one of the holes 185 is aligned with the cover mounting hole
in the outlet. With double.outlets, generally holes 185 will
be spaced so that they overlie the cover mounting holes in
each of the outlets, although a single hole 185 could be
aligned with the hole in one of the outlets to accept the
securing screw. Conduit 170 may also be provided with a
resilient seal material 179, such as foam weatherstrip
material, secured to the first end about opening 171.
Generally, it is preferred that mounting screws 175 not
extend unduly far into an electrical box 177, Fig. 23, when
the conduit 170 (or conduits of other embodiments) is
installed over the opening 172 in the wall. Should screws 175
extend deeply into the box, they may contact and displace
wires in the box. Also, with some boxes, screws can only be
inserted to a limited depth. In addition, the farther the
screws 175 extend into the box 177, the more turns, and
therefore time, required for tightening the screws while
installing conduit 170 over the opening 172 in the wall.
While electrical boxes 177 are required by building codes to
be installed at a standard depth in the opening 172 in a wall,
in practice, considerable variation has been found in the
depth of boxes 177.
Provision of a thickness of resilient material 179,
particularly of a relatively easily compressed foam seal
material, permits use of conduit 170 with mounting screws 175
of a single, fixed length even if the electrical box 177 or
electrical device 178 is not set at the exact standard depth
in the opening 172 in the wall. In the event that the box 177
has been mounted shallowly in opening 172, i.e., the front of
the box extends out slightly further than the surrounding wall
surface, the foam seal material need not be compressed while
installing conduit 170 over the opening 172. The uncompressed
foam seal material 179 will suffice to direct most of the
18
airflow through the electrical box 177 and its mounting
opening 172. Should the box 177 be mounted deeply in opening
172 , i . a . , the front of the box is behind the surrounding wall
surface, the foam seal material may be compressed to reduce
the distance from the screw holes 174 and 185 in the conduit
170 to the wall surface 180, thereby allowing the single
length mounting screws 175 to reach the threaded screw
receiving holes 176.
A lip 181 may be provided about the outside circumference
of the first end of conduit 170. The lip 181 helps to guide
installation of the foam seal material 179 about opening 171
of conduit 170, and also protects the foam seal material and
helps hold it from being knocked off of the front end of
conduit 170. It may also serve to help retain foam seal
material 179 about opening 171 when pressurized air is applied
to conduit 170.
The present invention accelerates drying of a wall or
ceiling by inducing an exchange of moisture saturated air from
the space within the wall or ceiling with unsaturated air from
the environment. As indicated, the exchange of air can occur
by forcing air into the wall or by drawing air out of the
wall. A combination can also be used where one blower unit
20 can be used to force air into a wall or ceiling through
some electrical boxes, while a second blower unit 20 can be
used to draw air out of the wall or ceiling at different
locations through other electrical boxes. A dehumidifier can
be provided in the room to remove moisture from the air before
it enters the wall. Air forced into a wall could come from
a remote location outside the room having air drier than the
air in the room being dried.
The conduits of the invention are preferably made from
a clear plastic material so that a user can see through the
conduit and thereby guide the mounting screws through the
mounting holes in the conduit to the threaded screw-receiving
holes in either the electrical box or the electrical devices
2~6Q'~~ a
19
mounted in the electrical box to which the conduit is to be
secured.
While the conduits shown all have generally rectangular
first ends, various other shapes, such as circular could be
used. This is particularly the case if the conduit is to be
used over a circular electrical box such as sometimes used in
ceilings. Also various transitions between the first end and
second ends could be used with various configurations used at
the second end for coupling to an air hose.
Further, while the conduits have been shown as secured
around the electrical boxes with screws attaching the conduits
to a wall switch, outlet, or the box itself, other means could
be provided to secure the conduit to an electrical box such
as arms extending from the conduit to fit inside the
electrical box to removably hold the conduit thereto. The
conduit can be constructed of plastic or other materials or
can be molded of a plastic material.
Devices for generating an air pressure differential,
i.e., pressurized air or partial vacuum other than the
centrifugal-flow blower unit 20 shown may be used in the
present invention. It is important that the pressure
difference of the partial vacuum or pressurized air be
sufficiently low that the difference in pressure across
plasterboard 51 will not cause damage to the plasterboard 51.
Similarly, a spring catch as commonly used with vacuum cleaner
hoses may be used to retain the hoses on nipples and conduits
in lieu of the hose clamps 47 and 68 shown.
While electrical boxes have been described specifically
as those boxes for mounting electrical wall switches and
outlets, electrical boxes include various other electrical
boxes or similar boxes installed in walls, ceilings, or floors
could be used, such as those which house telephone jacks,
television cables, video cables, or computer cables.
Further, if desired to bias the conduit against a wall
around the box and opening therefor, springs could be provided
20
between the conduit and the heads of the screws securing the
conduit to the boxes. Other bias means could also be used.
Whereas this invention is here illustrated and described
with reference to embodiments thereof presently contemplated
as the best mode of carrying out such invention in actual
practice, it is to be understood that various changes may be
made in adapting the invention to different embodiments
without departing from the broader inventive concepts
disclosed herein and comprehended by the claims that follow.
